I'm just playing around with some settings in the Car-Adapter-Mode. First off
all, we do have the delay in resume play if you unplug and plug the charger again.

If I'm right this is be done with the following line in powermgmt.c:

play_resume_time = current_tick + HZ*5;

So "5" is the multiplicator and let me adjust the time when play will be resumed.

Since we do have the auto-startup-feature implemented which will automaticly
boot Rockbox if the charger is connected. The device than jumps into play
without any delays which will confuse my radio a bit.

So what I want is the same delay on resume play when booting, as we have for the
unplug/plug resume.